Most of the matter in the Universe is dark; determining the composition and interactions of this dark matter are among the defining challenges in particle physics today. I will summarize the present status of dark matter searches and the case for exploration beyond the WIMP paradigm, particularly the motivations for “light dark matter” close to but beneath the weak scale. I will also describe sharp milestones in sensitivity needed to decisively explore the best-motivated light dark matter scenarios, and comment on experimental techniques to reach these milestones.